I have to migrate from a CUCM-BE w/ CUCM 6.1 and Unity Connection 2.1 to a separated CUCM 7.x and Unity Connection 2.x or 7.x environment.
It's critical that we try to backup and restore as much Unity Connection data as possible especially subscribers, messages, recorded names and greetings.
The only way I can possibly see doing this is upgrading the CUCM-BE to 7.x, using COBRAS to do an export and then import onto the standalone Unity Connection 7.x system.
Is this the only way and is it possible?
COBRAS cannot be used to export Connection 2.0 or 2.1 systems (1.2, 7.x, 8.x only). The off box access to data was not fully enabled in the 2.x line and COBRAS cannot get what it needs.
You can migrate from a CUCMBE install of 7.x - however you'd leave suscriber PIN (phone passwords) behind. Those are managed by Call Manager in that deployment and they are not available for off box extraction. But other than that you'd get everything you need.
So one option may be to upgrade to CUCMBE 7.x, get a COBRAS export and then import to your stand alone install. If the PIN's having to be reset isn't a show-stopper that may work for you.